Certs: pass course name on queue

Stanford had a problem a few times that certificate requests had
different values for the course display name and the course name printed
on the certificate and verification pages because of human error. This
passes the course display name on the queue to the certificate requests,
so that at least one place where the course name is reproduced (the
certificate agent's settings.py) can be eliminated.
Modifying the checkbox examples syntax so that it works in studio.edge.edx.org now.
Adding my name to the AUTHORS file.
Merge pull request #3554 from itsbenweeks/itsbenweeks/checkbox_doc_example_update

Modifying the checkbox examples syntax so that it works in studio.edge now.
Integrate event-tracking in to the LMS

Support incremental conversion of events from the old API to the new, in order to ensure the new system is working, enrollment events have been modified to make use of the new API.
Create a skeleton of event-tracking developer docs

A first pass at providing details about how to emit events, what to emit etc.
Merge pull request #3523 from mulby/gabe/tracking-shim

Integrate event-tracking in to the LMS
Merge pull request #3558 from mulby/gabe/event-tracking-doc

Create a skeleton of event-tracking developer docs
Merge pull request #3532 from edx/jrbl/certs_pass_course_name_in_dict

Certs: pass course name on queue
Tolerance expressed in percentage now computes correctly. [BLD-522]
Modified and extended tests on percentage expressed tolerance.
Addressed comments.